Hi there,
Thanks for reaching out. I’d be happy to help with your question.
If you are only going to use the plugin on 3 sites within your MultiSite network, you only technically need to purchase the Business license. However, in order for automatic updates to work on a MultiSite network, you would need the MultiSite license.
If you don’t mind manually updating the plugins, I think the Business license is the way to go for your specific needs.
Hope that helps! Please let me know if you have any additional questions about this.
Thanks,
Sky